The present invention relates to stoppers, in particular for use with liquid specimen tubes. More particularly, it is applicable to tubes for sampling of blood under vacuum.
To collect blood for the purpose of analysis, a flexible tube including a needle at each end may be used. One of the needles is inserted into the vein, while the other serves for the perforation of the stopper of the tube under vacuum. Experience proves that the withdrawal of the needle leaves traces of blood on the head of the stopper, which entails a risk of contamination of personnel involved with handling of the tube containing the stopper.